Abscisic acid is a naturally occurring plant hormone which has been found to be useful in the treatment of a vitamin deficiency in man, animal and the avian species. See U.S. Pat. No. 3,958,025 to Livingston. This hormone has been used to delay budbreak of certain plants and thereby to exert an insect control effect. This approach is based upon reducing the food supply available to phytophagous insects. See D.C. Eidt and C.H.A. Little, The Canadian Entomologist, 100, 1278-1279 (1968). This hormone has also been tested for its effect, when ingested, on spruce budworm. See D.C. Eidt and C.H.A. Little, Journal of Economic Entomology, 63, 1966-1968 (1970). Eidt and Little conclude that the development of the budworm is not affected and state that their data is inconclusive as to affects on pupal size, development time, fecundity, and egg viability since the number of budworms tested was too small. S. Scheurer, in The Host-Plant in Relation to Insect Behavior and Reproduction, T. Jeremy, Ed., Plenum Press, New York, pp. 255-259 (1976), reports that when plants of Vicia sp. are treated with abscisic acid and fed to aphids, there is observed an increased size of the V.sub.1 offspring, a decrease in maturation time, and an increase in reproduction of the V.sub.1 offspring. The chemistry and physiology of abscisic acid and its analogs are described by Milborrow, Ann. Rev. Plant Physiol., 1974, 25. 259-307.
In addition to the above art, I am aware of approaches to insect control which require chemical substances such as the chlorinated hydrocarbons. These approaches, however, have the disadvantage of employing substances which are not limited in toxicity to insects.